1. Technical Field
The present invention relates to a distributed processing technique for a master calculator (hereinafter referred to simply as “a master”) to cause multiple worker calculators (hereinafter referred to simply as “workers”) to perform distributed processing through a series of processing groups.
2. Description of the Related Art
Conventionally, in the flow of processing passed between a master and a worker, which can communicate with each other via a network, the master throws processing (including data required for execution thereof) into the worker. Next, the worker into which the processing has been thrown executes the processing. Then, the worker returns the execution result of the processing to the master. By performing this with multiple workers, the master causes the workers to perform distributed processing of the whole processing.
Japanese Laid-open Patent Publication No. H9-73432, there discloses a technique in which processing of one or more transactions to be processed by the same processing process is requested collectively, in an online distributed system. Specifically, a processing process for processing transaction data is disclosed. Then, in online control processing for passing the transaction data to the processing process, one or more transactions to be processed by the same processing process, among transactions waiting to be processed, are collected and passed to the processing process by one processing request.
Japanese Laid-open Patent Publication No. 2004-110318 discloses a technique in which processing is assigned in units of task groups, each of which is constituted by multiple tasks. Specifically, an upper management apparatus assigns processing of a task group to a lower management apparatus. Then, the lower management apparatus assigns tasks included in the task group to task execution apparatuses. The task execution apparatuses execute the tasks and transmit execution results to the lower management apparatus. Then, the lower management apparatus collects the task execution results and transmits the collected results to the upper management apparatus. At the end, the upper management apparatus puts the collected results together and outputs them.
However, in the above prior-art technique disclosed in Japanese Laid-open Patent Publication No. H9-73432, there is no mention of how many transactions are collected and passed to the processing process, though it has a great influence on the efficiency of the distributed processing.
For example, if the number of transactions to be collected is increased, the number of transmissions of a processing request can be reduced. However, the response time required until obtaining the result of the execution is increased. Furthermore, if too many transactions are collected, there may be a case, when the number of usable workers increases, it is not possible to equally assign transactions to the workers.
Furthermore, when there are a small number of usable workers, there is a possibility that, when the number of transactions in a queue decreases, all the transactions are to be processed by one worker. Thus, if transactions are inappropriately collected, a problem is caused that usable workers cannot be sufficiently utilized and, consequently, the time required for the distributed processing is lengthened.
In the above prior-art technique disclosed in Japanese Laid-open Patent Publication No. 2004-110318 also, there is no mention of the number of tasks constituting a task group (the number of tasks to be collected), and there is a problem that usable workers cannot be sufficiently utilized and, consequently, the time required for the distributed processing is lengthened.
The object of the present invention is to provide a distributed processing technique capable of reducing communication traffic between the master and the worker and improving the efficiency of distributed processing by assigning a processing group in which processings, the execution time for each of which is short, are appropriately collected, in order to solve the problems of the conventional techniques disclosed above.